To increase efficiency in the search for resources, many animals rely on their spatial abilities. Specifically, primates have been reported to use mostly topological and rarely Euclidean maps when navigating in large-scale space. Here, we aimed to investigate if the navigation of wild common marmosets inhabiting a semiarid environment is consistent with a topological representation and how environmental factors affect navigation. We collected 497 h of direct behavioral and GPS information on a group of marmosets using a 2-min instantaneous focal animal sampling technique. We found that our study group reused not only long-route segments (mean of 1007 m) but entire daily routes, a pattern that is not commonly seen in primates. The most frequently reused route segments were the ones closer to feeding sites, distant to resting sites, and in areas sparse in tree vegetation. We also identified a total of 56 clustered direction change points indicating that the group modified their direction of travel. These changes in direction were influenced by their close proximity to resting and feeding sites. Despite our small sample size, the obtained results are important and consistent with the contention that common marmosets navigate using a topological map that seems to benefit these animals in response to the exploitation of clustered exudate trees. Based on our findings, we hypothesize that the Caatinga landscape imposes physical restrictions in our group’s navigation such as gaps in vegetation, small trees and xerophytic plants. This study, based on preliminary evidence, raises the question of whether navigation patterns are an intrinsic characteristic of a species or are ecologically dependent and change according to the environment.
This study used the interpersonal–psychological theory of suicide to explore the relationships among DSM-5 posttraumatic stress disorder (PTSD) symptom clusters derived from the six-factor anhedonia model and facets of acquired capability for suicide (ACS). In a sample of 373 trauma-exposed undergraduates, most PTSD symptom clusters were negatively associated with facets of ACS in bivariate correlations, but the anhedonia cluster was positively associated with ACS in regression models. Structure coefficients and commonality analysis indicated that anhedonia served as a suppressor variable for the other symptom clusters. Our findings further elucidate the complex relationship between specific PTSD symptom clusters and ACS. 相似文献
This study compared the direction of source confusions and the effect of predictability on reality monitoring for internally generated information and externally derived information in younger (mean age 19-25) and older (mean age 70-85) adults. Participants were invited to listen to the conclusions of simple stories or to generate and imagine them. Conclusions could be either highly predictable (Experiment 1) or unpredictable (Experiment 2). The change in predictability produced changes in the direction of source confusions only in older adults. When a story ended in a predictable way, older adults attributed to imagination conclusions that were actually perceived, whereas the pattern of confusions tended to reverse with unpredictable stories. 相似文献
This study examines J. H. Flavell, S. G. Shipstead, and K. Croft's (1978) finding that 2 1/2-year-old children can hide an object behind a screen but cannot achieve the same result by placing the screen in front of the object. Experiment 1 replicated this finding alongside a task in which children judged what a person in a picture was looking at. Performance on the move-object task approached ceiling; performances on the move-screen and looking-where tasks were highly correlated even after age and control task performance were partialed out (r = .54, p < .01). Experiment 2 examined whether the finding resulted because the object was more interesting to manipulate than the screen. The move-object task remained easier than the move-screen task with an interesting screen and a dull object. The move-screen task again correlated specifically with the looking-where task. Results are explained in terms of engagement, a precursor to a mature understanding of attention. 相似文献
Olivopontocerebellar atrophy (OPCA) is a still debated condition, of which motor disruption is the most common feature. A high incidence of associated mood disorders may exist, but there are few studies on concomitant cognitive impairment. Our aim was to assess whether there is reading and writing disruption in olivopontocerebellar atrophy (OPCA). 6 patients were administered different reading and writing tasks. Scores were then compared to those obtained by healthy volunteers. There was an evident impairment in reading and writing execution in our patients compared to those of the control group. On the contrary, no difference could be found in abstraction, problem-solving, and memory tasks. We discuss the results, debating the role of the cerebellum in the conscious process of cognition or in ocular movement control (necessary for reading and writing fluidity and effective execution) and in the dynamic activation of all the cerebral cortex mediated by the diffuse projection to the reticular system. 相似文献